Automatic adjustment of data replication based on data access

ABSTRACT

A processor determines a predicted quantity of updates to be made to a set of data using a history of updates. The set of data is associated with a category of replication that indicates a first frequency of data replication to be applied to the set of data. The processor determines whether the first predicted quantity of updates meets a first threshold for a frequency of replication of the set of data. The first threshold indicates an allowed number of updates and meeting the first threshold indicates that an adjustment to the frequency of replication of the set of data is to be initiated. The processor responds to a determination that the first threshold has been met by associating the set of data with a category of replication that has a second frequency of data replication to be applied to the set of data.

BACKGROUND OF THE INVENTION

The present invention relates generally to the field of datareplication, and more particularly to changing types of datareplication.

Within the scope of enterprise storage systems, there are various typesof data replication. Data replication can be used for a variety ofpurposes, including disaster recovery, high availability, and businesscontinuance. Often times, data replication solutions that offer a highertier of data protection also have higher requirements on the replicationenvironment. For example, single site copies, such as snapshots, can beperformed relatively quickly with little to no impact to applications.However, copies that require site to site communication, or may evenspan more than two sites, incur either additional latency for the host(as in synchronous solutions), or potential delays between when a writeis stored on the source storage system and when that data is protectedby a copy on a remote site (asynchronous solutions). Environmentalrequirements, like more bandwidth between the sites, can lead toadditional costs to the customer in order to avoid impacting theapplication.

SUMMARY

Embodiments of the present invention provide a method, system, andprogram product for modifying a frequency of replication of a set ofdata. A processor determines first predicted quantity of updates thatare likely to be made to a set of data based, at least in part, on ahistory of updates for the set of data. The set of data is associatedwith a first category of replication that indicates a first frequency ofdata replication to be applied to the set of data. The processordetermines whether the first predicted quantity meets a first thresholdfor a frequency of replication of the set of data, wherein the firstthreshold indicates an allowed number of updates for the set of data,and wherein a meeting of the first threshold indicates that anadjustment to the first frequency of replication of the set of data isto be initiated. The processor predicts a degree of latency that will beexperienced during replication of the set of data. The processordetermines whether the first predicted quantity meets a plurality ofthresholds for the frequency of replication of the set of data. Theprocessor responds to a determination that the first predicted quantitymeets the plurality of thresholds by identifying a threshold, includedin the plurality of thresholds, that has the highest priority. Theprocessor responds to a determination that the first threshold has beenmet by associating the set of data with a second category ofreplication. The second category of replication indicates a secondfrequency of data replication to be applied to the set of data. Theassociation of the set of data with the second category of replicationis based, at least in part, on i) the threshold that has the highestpriority and ii) the predicted degree of latency meeting a thirdthreshold. The third threshold indicates a degree of latency that isallowed for given mode of data transmission. The processor associatesthe second category of replication with at least one of i) a type ofstorage media to be used during the replication of the set of data, ii)a mode of data transmission to be used during the replication of the setof data, and iii) a type of data that represents the set of data duringthe replication of the set of data. The associating is based, at leastin part, on the first predicted quantity meeting a second threshold forthe frequency of replication of the set of data. The second thresholdbeing met indicates at least one of i) the type of storage media to beused during the replication of the set of data, ii) the mode of datatransmission to be used during the replication of the set of data, andiii) the type of data that represents the set of data during thereplication of the set of data. The processor responds to adetermination that the first threshold has been met by delaying, for apredetermined period of time, a determination as to whether a secondpredicted quantity of updates that are likely to be made to the set ofdata meets a third threshold for the frequency of replication of the setof data. The delay allows for completion of a normalization processfollowing replication of the set of data.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a functional block diagram illustrating a data replicationenvironment, in accordance with an exemplary embodiment of the presentinvention.

FIG. 2 illustrates operational processes of a replication program,executing on a computing device within the environment of FIG. 1, inaccordance with an exemplary embodiment of the present invention.

FIG. 3 depicts a block diagram of components of the computing deviceexecuting replication program, in accordance with an exemplaryembodiment of the present invention.

DETAILED DESCRIPTION

Hierarchical storage management (HSM) is a data storage technique, whichautomatically moves data between high-cost and low-cost storage media.HSM systems exist because high-speed storage devices, such as hard diskdrive arrays, are, in general, more expensive (per byte stored) thanslower devices, such as optical discs and magnetic tape drives. Astorage tier indicates a collection of storage devices of a particulartype of storage that can be, or is to be, used to store a givenpartitioned volume. In general there are two transfer modes that can beused to transfer the partitioned volume for storage from one storagetier to another, namely synchronous and asynchronous. In a synchronoustransfer mode, the data write either completes on both a primary storagedevice and a secondary storage device or not at all. In contrast, in anasynchronous transfer mode, the write is considered complete as soon asa single storage device, of a plurality of storage devices that are tocomplete the write, acknowledges the write as complete, i.e., the writeto the primary storage device and a secondary storage device are notdependent on one another for completion.

The closest known solutions dynamically modify the transfer mode of datastorage from synchronous to asynchronous based on the latency and inputand output (I/O) transfer rate between the source and target storagedevices. Known solutions dynamically modify a plurality of transfermodes for a partitioned volume based on the access rate for I/O on theprimary storage system. Such solutions are, in some cases, based on analgorithm for dynamically changing the transfer modes based on athreshold policy associated with the degree of impact such transfers maybe causing an application. As such, these known solutions are directedto manipulation of a storage tier and the transfer mode to be utilized,not a replication category. A replication category indicates how often agiven set of data, which is not limited to a partitioned volume, shouldbe backed up or copied from one location to another. In general, a setof data that is rarely accessed will be less likely to need backup,since it likely has not changed.

In contrast to known solutions that address storage tiers, embodimentsof the present invention are directed to replication categories. Inaddition, embodiments of the present invention are not focused solely onthe I/O transfer between sites. In contrast, embodiments of the presentinvention are directed to the control of replication of a set of databased on the I/O rates to those sets of data. Embodiments of the presentinvention recognize that the number of I/O updates to a set of data canbe used to indicate the importance of a set of data for replicationpurposes, i.e., I/O events, to the individual sets of data can be usedto indicate the “importance” of those sets of data and thus how oftenthey should be replicated. This means that the decision to switchbetween replication categories occur at the level of a set of data, asopposed to occurring at the level of a storage tier of a site.

As such, embodiments of the present invention are directed to the“importance” of the set of data as the primary characteristic thatdetermines a replication category for a given set of data. A replicationcategory is a category of data replication that is associated with a setof data, thereby controlling how frequently that set of data isreplicated. This allows a replication system to dynamically move the setof data between different categories of replication to provide betterbackup consistency for all sets of data, regardless of how often theyare accessed. This means that the decision to switch between differentreplication categories happens at a set of data level based on therelative importance of the set of data, as opposed to being solely tiedto the I/O frequency and application impact.

Embodiments of the present invention recognize one or more of thefollowing: i) that replication of a set of data needs may not be static;ii) during certain time periods, there are fluctuations in the rates ofI/O to certain sets of data, i.e., reads and writes, to a given set ofdata during one time period can be higher or lower than during othertime periods; iii) (iii) bandwidth requirements for synchronousreplication fluctuate in proportion to the rate of I/O to the site beingreplicated; (iv) a high bandwidth connection can be costly; (v) a highbandwidth connection may be underutilized during periods of low I/Oactivity at the site being replicated, which is wasteful; and vi) that aproactive approach can be used to predict future I/O rate for aparticular set of data and that a replication category of a set of datacan be adjusted accordingly.

Embodiments of the present invention dynamically change the rates ofreplication, i.e., replication categories, of sets of data based onchanging I/O rates to the sets of data. In other words, embodiments ofthe present invention change the replication category of a set of dataautomatically based upon changing host I/O rates of that set of data.Embodiments of the present invention address not only dynamicallycreating new copy relationships, but converting between different copyrelationship types. There are multiple criteria which could be used tochange the replication category.

In certain embodiments of the present invention, some users may preferto change replication category based on host impact with the purpose ofreducing host impact. For instance, a synchronous copy may have moreimpact than an asynchronous copy. In such a case, higher I/O to a set ofdata could trigger a less impactful replication. In certain embodimentsof the present invention, users may prefer to change replicationcategory based on data importance, where more heavily used sets of dataare considered more important. In such a case, higher I/O to a set ofdata could trigger greater data protection, such as more sites for usein replication, more frequent replication, more copies of data, or acombination thereof.

In certain embodiments of the present invention, for replication typeswhere a greater level of data protection results in more host impact, apolicy can be used to determine whether to prefer less impactfulreplication or to prefer greater data importance.

The present invention will now be described in detail with reference tothe Figures. FIG. 1 is a functional block diagram illustrating a datareplication environment, generally designated 100, in accordance withone embodiment of the present invention. Data replication environment100 includes computing device I/O and computing device 120 connectedover network 130. Computing device I/O includes replication program 115,system data 116, and volumes 117.

In various embodiments of the present invention, computing device I/Oand computing device 120 are respectively a computing device that can bea standalone device, a server, a laptop computer, a tablet computer, anetbook computer, a personal computer (PC), or a desktop computer. Inanother embodiment, computing device I/O and computing device 120respectively represent a computing system utilizing clustered computersand components to act as a single pool of seamless resources. Ingeneral, computing device I/O and computing device 120 respectively canbe any computing device or a combination of devices with access toreplication program 115 and volumes 117 and is capable of executingreplication program 115. Computing device I/O and computing device 120respectively may include internal and external hardware components, asdepicted and described in further detail with respect to FIG. 3.

In this exemplary embodiment, replication program 115, system data 116and volumes 117 are stored on computing device I/O. However, in otherembodiments, replication program 115, system data 116 and volumes 117may be stored externally and accessed through a communication network,such as network 130. Network 130 can be, for example, a local areanetwork (LAN), a wide area network (WAN) such as the Internet, or acombination of the two, and may include wired, wireless, fiber optic orany other connection known in the art. In general, network 130 can beany combination of connections and protocols that will supportcommunications between computing device I/O, computing device 120,replication program 115, system data 116 and volumes 117, in accordancewith a desired embodiment of the present invention.

In exemplary embodiments, replication program 115 monitors the levels ofaccess of sets of data included in volumes 117. Replication program 115determines an importance rating for each set of data based on thechanging I/O rates for each respective set of data. Replication program115 dynamically changes the respective replication category of thosesets of data based, at least in part, on their importance rating and inresponse to the importance rating changing beyond a threshold.Replication program 115 includes a number of thresholds that replicationprogram 115 uses to determine whether or not an adjustment to areplication category of a set of data is needed and, if so, whether thelevel of replication should be increased or decreased. In someembodiments, replication program 115 monitors and utilizes a heat map toidentify the importance of a given set of data. In such embodiments, thevalues of such a heat map reflect the number of I/O events and changingI/O rates for each respective set of data.

In exemplary embodiments, system data 116 includes records that indicatethe I/O for respective sets of data included in volumes 117, e.g., aheat map, as well as the current (which can be measured), historical,and predicted latency between computing device I/O and 120. In general,a heat map is a visual representation of workload activity metrics for aset of data that is stored as heat values. A workload activity metricmay be calculated for a set of data included in a logical volume, suchas extents. The heat value may be a number on a scale and may beexpressed as a temperature gradient from hot (high activity) to cold(low activity). In exemplary embodiments, volumes 117 is a database ofsets of data that are accessed by users, via network 130, therebygenerating the data I/O for respective sets of data that is stored aspart of system data 116.

In this embodiment, computing device I/O serves as a primary storagesite for volumes 117 and computing device 120 serves as a secondarystorage site, i.e., a backup site, for volumes 117.

FIG. 2 illustrates a flowchart, 200, illustrating operational processesof replication program 115, executing on computing device I/O within theenvironment of FIG. 1, in accordance with an exemplary embodiment of thepresent invention.

In process 210, replication program 115 predicts a future degree of I/Ofor the sets of data included in volumes 117 based on the historical I/Oof those sets of data as indicated by the information included in systemdata 116. For example, a set of data, A3, was accessed and updated 2,800to 3,000 times during the first and fourth quarters of the previousyear. However, A3 was accessed less than one hundred times in each ofthe second and third quarters. Based on this data, replication program115 predicts that there is a high probability that A3 will experience ahigh set of data of I/O during the first and fourth quarters of thisyear relative to the second and third quarters of this year.

In process 220, replication program 115 predicts a future degree oflatency between computing device I/O and computing device 120 based onthe historical latency as indicated by the information included insystem data 116. For example, during business hours of a five dayperiod, Monday through Friday, last week, there was a high degree oflatency between computing device I/O and computing device 120 during thehours of 2 pm and 5 pm. However, there was a very low degree of latencybetween computing device I/O and computing device 120 during the hoursof 7 am until 1 pm. Replication program 115 accesses system data 116 anddetermines that the current latency is likely to be high because thecurrent day of the week is Wednesday and the time is 3 pm. Based on thisdata, replication program 115 predicts that the latency will remain highfor the next two hours. In certain embodiments, replication program 115directly tests for and determines the actual latency between computingdevice I/O and computing device 120.

In decision process 230, replication program 115 determines whether athreshold has been met, such that an adjustment to a replicationcategory of a set of data is needed. For example, a threshold, T1,directed to I/O rates, dictates that an adjustment to a replicationcategory of a set of data is required and that a synchronous transfermode is utilized during replication if the I/O rate of that set of dataexceeds five hundred operations during a particular period of time. Ifthe I/O rate for a set of data, B7, has exceeded T1, then replicationprogram 115 determines that an adjustment to a replication category ofB7 is needed and that a synchronous transfer mode is to be utilizedduring replication. Continuing with the previous example, the I/O ratefor set of data, C9, has exceeded T1. However, the latency betweencomputing device I/O and computing device 120 has exceeded a threshold,T2, which dictates whether or not a synchronous transfer mode can beused during replication. As such, replication program 115 determinesthat an adjustment to a replication category of C9 is needed, since T1was exceeded, and that, since T2 was also exceeded, a synchronoustransfer mode cannot be used during replication. As such, apoint-in-time or asynchronous transfer mode is used to backup C9,regardless of the number of backups required over a given time periodand the requirements of T1, i.e., the dictated requirements of T2 takepriority over the requirements of T1 if both thresholds have been met.If a threshold has been met such that an adjustment to a replicationcategory of a set of data is needed (decision process 230, yes branch),then replication program 115 proceeds to decision process 250. If athreshold has not been met such that an adjustment to a replicationcategory of a set of data is not needed (decision process 230, nobranch), then replication program 115 proceeds to process 240.

In process 240, replication program 115 delays for a predeterminedperiod of time. Replication program 115 delays further processing toprevent unnecessary adjustments to replication levels. Typically, aperiod of time is required for normalization of the replication processto occur. As such, a delay is used by replication program 115 to allowsuch normalization to complete. This delay also reduces wasteful use ofcomputing resources by limiting how often replication program 115 checkswhether or not a threshold has been met.

In decision process 250, replication program 115 determines if multiplethresholds have been met. If multiple thresholds have been met (decisionprocess 250, yes branch), then replication program 115 proceeds toprocess 260. If multiple thresholds have not been met (decision process250, no branch), then replication program 115 flags the threshold thatwas met and proceeds to process 270.

In process 260, replication program 115 determines which of thethresholds has the highest priority. For example, thresholds that aredirected to I/O rates for sets of data s would have a higher prioritythan thresholds for latency. In another example, two thresholds for I/Ohave been met. The first threshold is a number of I/O events to a givenset of data over the time period of one year. The second threshold is anumber of I/O events to a given set of data over the time period of oneweek. Since the second threshold yields a more immediate indication offuture I/O events for the set of data, replication program 115determines that the second threshold has the higher priority. Thethreshold with the highest determined priority is then flagged.

In process 270, replication program 115 identifies which threshold is tobe used, i.e., which threshold has been flagged. In process 280,replication program 115 modifies the replication category based on theidentified threshold. In some cases, the frequency of replication for agiven set of data is increased, in other cases that frequency isdecreased. In other words, a set of data is assigned to a tier ofreplication, with an associated frequency of set of data replication,based on which threshold has been met that has the highest priority.

In process 290, replication program 115 determines an appropriatestorage type, i.e., a type of storage media, and transfer mode, i.e., amode of data transmission, which will best facilitate the frequency ofreplication for a given set of data. This is often based on thecircumstances of the given set of data, e.g., which thresholds have beenmet and the predicted number of I/O events for that set of data. Forexample, a set of data that is assigned to a tier of replication with anassociated high frequency of set of data replication may benefit mostfrom the use of a high speed storage system and synchronous datatransfer when replicating that set of data. However, in somecircumstances, the type of storage used or the transfer mode is modifiedbased on which thresholds have been met, such that the resulting tier ofreplication is, in general, not optimally paired with a storage tier andtransfer mode, but is optimally paired based on thresholds being met,i.e., the current circumstances. For example, a set of data that isassigned to a tier of replication with an associated high frequency ofset of data replication would benefit most from the use of a high speedstorage system and synchronous data transfer when replicating that setof data. However, due to a high latency threshold being met, anasynchronous data transfer is used when replicating that set of data.

In this embodiment, replication program 115 ends after completion ofprocess 290. In certain embodiments, replication program 115 proceeds toprocess 240 after completion of process 290. This allows for apredetermined period of time to pass such that a normalization of thereplication of the set of data is completed. In some embodiments, theprocesses of replication program 115 are repeated periodically. As such,changes in the replication category of a given set of data would oftennecessitate a delay to prevent an undesirable number of changes in areplication category of a given set of data.

In some embodiments, in addition to determining an appropriate storagetype and transfer mode that will best facilitate the frequency ofreplication for a given set of data, a type of representation isdetermined to be used to represent the set of data during thereplication of the set of data, e.g., a summary of the values includedin the data set.

FIG. 3 depicts a block diagram, 300, of respective components ofcomputing device I/O and 120, in accordance with an illustrativeembodiment of the present invention. It should be appreciated that FIG.3 provides only an illustration of one implementation and does not implyany limitations with regard to the environments in which differentembodiments may be implemented. Many modifications to the depictedenvironment may be made.

Computing device I/O and computing device 120 respectively includecommunications fabric 302, which provides communications betweencomputer processor(s) 304, memory 306, persistent storage 308,communications unit 310, and input/output (I/O) interface(s) 312.Communications fabric 302 can be implemented with any architecturedesigned for passing data and/or control information between processors(such as microprocessors, communications and network processors, etc.),system memory, peripheral devices, and any other hardware componentswithin a system. For example, communications fabric 302 can beimplemented with one or more buses.

Memory 306 and persistent storage 308 are computer-readable storagemedia. In this embodiment, memory 306 includes random access memory(RAM) 314 and cache memory 316. In general, memory 306 can include anysuitable volatile or non-volatile computer-readable storage media.

Replication program 115 and volumes 117 are stored in persistent storage308 for execution and/or access by one or more of the respectivecomputer processors 304 via one or more memories of memory 306. In thisembodiment, persistent storage 308 includes a magnetic hard disk drive.Alternatively, or in addition to a magnetic hard disk drive, persistentstorage 308 can include a solid state hard drive, a semiconductorstorage device, read-only memory (ROM), erasable programmable read-onlymemory (EPROM), flash memory, or any other computer-readable storagemedia that is capable of storing program instructions or digitalinformation.

The media used by persistent storage 308 may also be removable. Forexample, a removable hard drive may be used for persistent storage 308.Other examples include optical and magnetic disks, thumb drives, andsmart cards that are inserted into a drive for transfer onto anothercomputer-readable storage medium that is also part of persistent storage308.

Communications unit 310, in these examples, provides for communicationswith other data processing systems or devices, including resources ofnetwork 130. In these examples, communications unit 310 includes one ormore network interface cards. Communications unit 310 may providecommunications through the use of either or both physical and wirelesscommunications links. Replication program 115 and volumes 117 may bedownloaded to persistent storage 308 through communications unit 310.

I/O interface(s) 312 allows for input and output of data with otherdevices that may be respectively connected to computing device I/O orcomputing device 120. For example, I/O interface 312 may provide aconnection to external devices 318 such as a keyboard, keypad, a touchscreen, and/or some other suitable input device. External devices 318can also include portable computer-readable storage media such as, forexample, thumb drives, portable optical or magnetic disks, and memorycards. Software and data used to practice embodiments of the presentinvention, e.g., replication program 115 and volumes 117, can be storedon such portable computer-readable storage media and can be loaded ontopersistent storage 308 via I/O interface(s) 312. I/O interface(s) 312also connect to a display 320.

Display 320 provides a mechanism to display data to a user and may be,for example, a computer monitor, or a television screen.

The programs described herein are identified based upon the applicationfor which they are implemented in a specific embodiment of theinvention. However, it should be appreciated that any particular programnomenclature herein is used merely for convenience, and thus theinvention should not be limited to use solely in any specificapplication identified and/or implied by such nomenclature.

It is to be noted that the term(s) “Smalltalk” and the like may besubject to trademark rights in various jurisdictions throughout theworld and are used here only in reference to the products or servicesproperly denominated by the marks to the extent that such trademarkrights may exist.

The present invention may be a system, a method, and/or a computerprogram product. The computer program product may include a computerreadable storage medium (or media) having computer readable programinstructions thereon for causing a processor to carry out aspects of thepresent invention.

The computer readable storage medium can be a tangible device that canretain and store instructions for use by an instruction executiondevice. The computer readable storage medium may be, for example, but isnot limited to, an electronic storage device, a magnetic storage device,an optical storage device, an electromagnetic storage device, asemiconductor storage device, or any suitable combination of theforegoing. A non-exhaustive list of more specific examples of thecomputer readable storage medium includes the following: a portablecomputer diskette, a hard disk, a random access memory (RAM), aread-only memory (ROM), an erasable programmable read-only memory (EPROMor Flash memory), a static random access memory (SRAM), a portablecompact disc read-only memory (CD-ROM), a digital versatile disk (DVD),a memory stick, a floppy disk, a mechanically encoded device such aspunch-cards or raised structures in a groove having instructionsrecorded thereon, and any suitable combination of the foregoing. Acomputer readable storage medium, as used herein, is not to be construedas being transitory signals per se, such as radio waves or other freelypropagating electromagnetic waves, electromagnetic waves propagatingthrough a waveguide or other transmission media (e.g., light pulsespassing through a fiber-optic cable), or electrical signals transmittedthrough a wire.

Computer readable program instructions described herein can bedownloaded to respective computing/processing devices from a computerreadable storage medium or to an external computer or external storagedevice via a network, for example, the Internet, a local area network, awide area network and/or a wireless network. The network may comprisecopper transmission cables, optical transmission fibers, wirelesstransmission, routers, firewalls, switches, gateway computers and/oredge servers. A network adapter card or network interface in eachcomputing/processing device receives computer readable programinstructions from the network and forwards the computer readable programinstructions for storage in a computer readable storage medium withinthe respective computing/processing device.

Computer readable program instructions for carrying out operations ofthe present invention may be assembler instructions,instruction-set-architecture (ISA) instructions, machine instructions,machine dependent instructions, microcode, firmware instructions,state-setting data, or either source code or object code written in anycombination of one or more programming languages, including an objectoriented programming language such as Smalltalk, C++ or the like, andconventional procedural programming languages, such as the “C”programming language or similar programming languages. The computerreadable program instructions may execute entirely on the user'scomputer, partly on the user's computer, as a stand-alone softwarepackage, partly on the user's computer and partly on a remote computeror entirely on the remote computer or server. In the latter scenario,the remote computer may be connected to the user's computer through anytype of network, including a local area network (LAN) or a wide areanetwork (WAN), or the connection may be made to an external computer(for example, through the Internet using an Internet Service Provider).In some embodiments, electronic circuitry including, for example,programmable logic circuitry, field-programmable gate arrays (FPGA), orprogrammable logic arrays (PLA) may execute the computer readableprogram instructions by utilizing state information of the computerreadable program instructions to personalize the electronic circuitry,in order to perform aspects of the present invention.

Aspects of the present invention are described herein with reference toflowchart illustrations and/or block diagrams of methods, apparatus(systems), and computer program products according to embodiments of theinvention. It will be understood that each block of the flowchartillustrations and/or block diagrams, and combinations of blocks in theflowchart illustrations and/or block diagrams, can be implemented bycomputer readable program instructions.

These computer readable program instructions may be provided to aprocessor of a general purpose computer, special purpose computer, orother programmable data processing apparatus to produce a machine, suchthat the instructions, which execute via the processor of the computeror other programmable data processing apparatus, create means forimplementing the functions/acts specified in the flowchart and/or blockdiagram block or blocks. These computer readable program instructionsmay also be stored in a computer readable storage medium that can directa computer, a programmable data processing apparatus, and/or otherdevices to function in a particular manner, such that the computerreadable storage medium having instructions stored therein comprises anarticle of manufacture including instructions which implement aspects ofthe function/act specified in the flowchart and/or block diagram blockor blocks.

The computer readable program instructions may also be loaded onto acomputer, other programmable data processing apparatus, or other deviceto cause a series of operational steps to be performed on the computer,other programmable apparatus or other device to produce a computerimplemented process, such that the instructions which execute on thecomputer, other programmable apparatus, or other device implement thefunctions/acts specified in the flowchart and/or block diagram block orblocks.

The flowchart and block diagrams in the Figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods, and computer program products according to variousembodiments of the present invention. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof instructions, which comprises one or more executable instructions forimplementing the specified logical function(s). In some alternativeimplementations, the functions noted in the block may occur out of theorder noted in the figures. For example, two blocks shown in successionmay, in fact, be executed substantially concurrently, or the blocks maysometimes be executed in the reverse order, depending upon thefunctionality involved. It will also be noted that each block of theblock diagrams and/or flowchart illustration, and combinations of blocksin the block diagrams and/or flowchart illustration, can be implementedby special purpose hardware-based systems that perform the specifiedfunctions or acts or carry out combinations of special purpose hardwareand computer instructions.

What is claimed is:
 1. A method for modifying a frequency of replicationof a set of data, the method comprising: determining, by a processor, afirst predicted quantity of updates that are likely to be made to a setof data based, at least in part, on a history of updates for the set ofdata, wherein the set of data is associated with a first category ofreplication that indicates a first frequency of data replication to beapplied to the set of data; determining, by the processor, whether thefirst predicted quantity meets a first threshold for a frequency ofreplication of the set of data, wherein the first threshold indicates anallowed number of updates for the set of data, and wherein a meeting ofthe first threshold indicates that an adjustment to the first frequencyof replication of the set of data is to be initiated; predicting, by theprocessor, a degree of latency that will be experienced duringreplication of the set of data; determining, by the processor, whetherthe first predicted quantity meets a plurality of thresholds for thefrequency of replication of the set of data; responsive to adetermination that the first predicted quantity meets the plurality ofthresholds, identifying, by the processor, a threshold, included in theplurality of thresholds, that has the highest priority; responsive to adetermination that the first threshold has been met, associating, by theprocessor, the set of data with a second category of replication,wherein the second category of replication indicates a second frequencyof data replication to be applied to the set of data, and wherein theassociation of the set of data with the second category of replicationis based, at least in part, on i) the threshold that has the highestpriority and ii) the predicted degree of latency meeting a thirdthreshold, wherein the third threshold indicates a degree of latencythat is allowed for given mode of data transmission; associating, by theprocessor, the second category of replication with at least one of i) atype of storage media to be used during the replication of the set ofdata, ii) a mode of data transmission to be used during the replicationof the set of data, and iii) a type of data that represents the set ofdata during the replication of the set of data, wherein the associatingis based, at least in part, on the first predicted quantity meeting asecond threshold for the frequency of replication of the set of data,wherein the second threshold being met indicates at least one of i) thetype of storage media to be used during the replication of the set ofdata, ii) the mode of data transmission to be used during thereplication of the set of data, and iii) the type of data thatrepresents the set of data during the replication of the set of data;and responsive to a determination that the first threshold has been met,delaying, by the processor, for a predetermined period of time, adetermination as to whether a second predicted quantity of updates thatare likely to be made to the set of data meets a third threshold for thefrequency of replication of the set of data, wherein the delay allowsfor completion of a normalization process following replication of theset of data.